How to modify/customize/decompile Opera mini jar file?

I want to add user script like greasemonkey in Opera Mini. Is it possible?

One way, that i guess, to do is to decomplie the opera mini jar file. Then modify the code in such a way that it'll load the desired userscript. Then compile it back to jar file.

The question is, is there any so开发者_如何学Pythonftware which can decompile a jar file properly in readable format (source code) ?

no, this is not possible. The reason is that in Opera Min's client/server model for showing web pages, the JavaScript is executed by the server. AFAIK nothing you do inside the JAR can make a script run, because you would have to modify settings on the server to configure User JS.

(Since the server backend processes a gazillion pages per minute, you can probably tell why they are not likely to allow each user to configure extra random and possibly time-consuming scripts..)